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Increasing numbers of patients are being seen with the acquired immune deficiency syndrome (AIDS). An abnormal serology with a positive direct antiglobulin test has been observed in these patients and is usually not thought to contribute to significant clinical morbidity. We describe a patient with AIDS who presented with a severe hemolytic anemia which was not distinguishable clinically and serologically from the idiopathic form of autoimmune hemolytic anemia.  相似文献   
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Measurements of ionized and total calcium levels in supernatant plasma samples from citrated platelet concentrates (PCs) were made over 7 days of storage. Both ionized and total calcium increased significantly during the storage period: respectively, from 0.074 mM Ca2+ in fresh platelet-rich plasma to 0.084 mM in PCs stored for 7 days (p = 0.017), and from 1.94 mM total calcium to 2.06 mM (p = 0.014) over the same period. The increase in calcium was partially blocked by the addition of platelet activation inhibitors to the PCs. Platelet-poor plasma stored under similar conditions showed no significant change in ionized or total calcium, which indicated that the increases observed in PCs were due to the release of cellular calcium. Significant correlations (p less than 0.01) were found between ionized or total calcium levels and lactate concentration or pH, but not hypotonic shock recovery rate. The demonstration of non-zero levels of ionized calcium makes it likely that Ca2+-dependent enzyme systems such as calpain expression and thrombin generation are active in the plasma of citrated PCs and may contribute to the platelet storage lesion.  相似文献   
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Background:

Nonunion of intertrochanteric fractures is uncommon because there is excellent blood supply and good cancellous bone in the intertrochanteric region of the femur. A diagnosis of primary intertrochanteric nonunion is made when at least 15 weeks after the fracture there is radiological evidence of a fracture line, with either no callus (atrophic) or with callus that does not bridge the fracture site (hypertrophic). There is only one published series that exclusively describes seven primary nonunions of intertrochanteric fractures. The aim of the present study was to analyze the results of internal fixation, valgization with 135° dynamic hip screw (DHS), and bone grafting in patients with primary nonunion of intertrochanteric fractures.

Materials and Methods:

Eighteen patients with primary intertrochanteric nonunion were included in the study; 16 were male and 2 were female. The age range was 30–70 years (mean: 46.9 years). The mean duration since index injury was 8.5 months (range: 4–18 months). As per the AO classification, the fractures were 31A 1.1 (n=1), 1.2 (n=1), 2.2 (n=3), 2.3 (n=9), and 3.3 (n=4). Three patients had hypermobile nonunion and 15 had stiff nonunion. The surgical principle was excision of pseudarthrosis, if present (n=3); freshening of the bone ends; stable fixation with 135° DHS, with good proximal purchase; bone grafting; and valgization.

Results:

Union was achieved in all patients at an average of 5.62 months (range: 4–7 months). The Harris hip score improved from 38 points preoperatively to 86 postoperatively at healing. The average limb shortening improved by 2 cm (range: 1.5 cm–3 cm). There was no infection and pain at the hip at final follow-up in any of the cases. All patients were subjectively satisfied with the outcome. All were capable of full weight bearing on their affected limb.

Conclusion:

Union in primary nonunion of intertrochanteric fractures in physiologically young patients with a well-preserved femoral head and good bone stock can be achieved with internal fixation, valgization, and grafting procedures.  相似文献   
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